Cook your pasta in a pot of well salted boiling water, reserving a cup of pasta water before draining.
Melt the butter in a large frying pan over medium heat.
Let it foam up slightly then add the pepper and stir.
Add the garlic paste and whisk (you don't need to add all of it, I love garlic so add it to taste!)
Add the cream and whisk, lowering the heat so it stays at only a very gentle simmer.
Add the lemon juice and zest and whisk again.
Add the parmesan in a few additions, whisking and letting it melt between each one.
Let it gently simmer for a couple of minutes until it thickens slightly.
Add the cooked pasta straight into the sauce with ¼ cup of pasta water and let it bubble for a minute so the sauce clings to the pasta. Add more pasta water as needed to loosen.
My biggest tip is that you want it on the saucier side so add more pasta water if you need it to loosen. Pasta soaks up sauce quickly so by making it super saucy in the pan then by the time you serve it into bowls it will be perfect!
I like to top the pasta with extra lemon zest and some red pepper flakes.